Filter



May 26, 1942. A. D. REDNER FILTER Filed Nov. 15, 1937 Patented May 26,1942 FILTER Arthur D. Redner, Detroit, Mich., assignor to GeneralFilters Inc., Detroit, Mich., a corporation of Michigan ApplicationNovember 15, 1937, Serial No. 174,502

(Cl. .2m-131) Z Claims.

This invention relates to iilters and particularly to lters intended tobe used in ltering the engine oil of internal combustion engines, thoughit isnot necessarily restricted to such use.

One of the objects of the invention is the provision of a. iilter of theVclass described wherein the eiective filtering pressure is maintainedat a pre-determined value which is independent of the actual oilpressure so that the passage of the oil through the filtering materialmay take place under optimum pressure conditions.-

In the conventional type of iilter some diiil` culty is found in coldweather'operation. This isl largely due to the fact vthat when theengine and lter have not been operating both assume atmospherictemperature and, in cold weather, the lter proper may becomesubstantially impermeable because of the then high viscosity of the oilstanding within it. When engine operation is resumed, though the engineoil is quickly heated,A little or no filtering takes place due to thethen impermeability of the lter. It is another object of the inventionto avoid this effect by the provision of an automatic heat regulatingmeans whereby should the lter be used during cold weather substantiallyall of the oil to be filtered may be initially by-passed around thesurface area of the lter so as to warm the lter up to operatingtemperature after whichthe tribute the oil to a relatively large surfaceof the 4 line filtering material and prevent undue packing thereof.

A further object of the invention is to provide a iilter of the classdescribed with a cartridge showing the. general arrangement offparts anda. portion of the internal structure of the device.

Fig. 3 is an elevational view of the ltering cartridge, partly insection to show the construc- A tionof the cartridge.

As best indicated in Fig. 2, the device comprises a casing II having a'cylindrical side wall, an open top I2 formed by the knurled edge of theside wall, and a generally spherical or conical outwardly projectingbottom I3. An examination of Fig. 2 will disclose that the bottom I3 isprovided, at its outer portion, with a marginal ledge I4 lying 'in theradial plane of the casing II and, .at the center, with an extrudedportion I5 to which there is welded or otherwise suitably attached aninletnipple I6, extending upwardly into the sump or basin I8 formed bythe bottom I3. The inside Wall of the nipple I6 is threaded as at II toreceive the oil inlet conduit (not' shown) and the end of the nipple isclosed except for a small metering hole I9. At one side vthe containerII is suitably provided with an outlet orifice 2I in which there may beattached an outlet conduit (not shown). Suitable brackets 23 formounting the deviceon an automobile or other structure may be providedat the side oi the casing II.

Within the casing II there is located a cylindrical cartridge 24constructed of galvanized steel or other similar material and containingwithin it substances designed to cleanse and purify the engine oil. Thediameter of cartridge 24 is slightly less than the inside diameter ofthe casing II so as to provide therebetween an annular space 2B in whichoil may be received. In the embodiment shown in the drawingl thecartridge is constructed like the conventional tin can and has adownwardly extending rim 26 at the bottom of the cartridge which restsupon the 0 shoulder Il in thebottom of the casing II and of iilteringmaterial which is quickly and easily 45 invention will readily appearfrom a reading of 520 the following detailed description `thereofaccompanied by the drawing listed below.

Fig. 1 is a top plan view of the filter, partly in section.

divides the interior of the casing into two compartments, the sumpportion I8 below the rim 25, and the annular portion 26 above the rim 25and between the sides and top of the cartridge 24 and the casing II.cartridge 24 are each suitably perforated at numerous points 29 and 30in order to allow the oil to enter the cartridge at the bottom 'throughperforations 29, pass upwardly through the filtering material in theinterior of the cartridge and leave the same through the perforations 30at the top. For handling the cartridge, a suitable wire loop 3| may beprovided at the top.A The cartridge 24 is maintained in position withinthe container I I Fig. 2 is an elevational l,view partly in section55-by a cup-shapedcover plate 32; provided at its The bottom 21 and top28 of the .felt disc 42 and top screen 4I.

Spring .means 34 within the cover plate 32 and attachedthereto serve tourge the cartridge 24 into seated relationship with Vthe shoulder I4.

Suitable means may be providedfor securely fasteningthe ,cover rplate32to the.casing II and,. as shown in the drawing, may include a pair oflugs 35 fastenedon either side of the contain# er VI I andacross-arm 34engaged inthe lugs and provided at the center with a threadedmember3lfadaptedto force the cover 32 'into sealed relationship with thetop-edge' of` casing II.

Asy isbestillustrated in Fig. 3, the interior of the ltering cartridge24 is provided with sev'- eral diiferent screening and filteringmaterials designed and positioned to afford progressive screening,ftopermit access to and emcient use of substantially all of the finestiiltering material and to render the oil path through the linefilposiand 3l effect a preliminary secondly, they serve to conduct'theoil to and tering material substantially the same in-difi'erent partsof the cartridge. 'I'he cartridge 24 directly inwardly of the perforatedbottom 21 thereof, is provided with a coarse screen 38,. A similarscreen 33 of. double thickness lies directly inwardly` of thesides ofthe cartridge 24 and extends `upwardly approximately three-quarters theheight or the cartridge# Likewise in the middle there is a screened core4| which 'commences becomes substantially ata point approximately aquarter ofthe `dis tance up from thebottom .of the cartridge 24.

and extends to-the'top of the cartridge. Directly below the perforatedtop 23 of the cartridge are successively a ycoarse screen 4I, anda iinefelt disk 42. -The remaining part of the interior of the cartridge, thatis. the space between sides of screen core 4I nandthe side screen 3l andythe space between the bottom screen 3l and the felt disc 42 'and thebottom of screen core 4I is filled withvery fine filtering material 43.The operation of the device is as follows:

.The oil to be filtered enters through the intake nipple I4 at thebottom of the device and collects in the sump or basin I8 formed betweenn the curved bottoml3 of the casing and the bottom 21 of the containeror cartridge 24. The seal between the depending rim 25 and the shoulderI4 not being completely oil tight part of( the oil will escape upwardlyinto the annular space 24 between .the cartridge and the side wall ofthe container. The seal, however, will be sufficiently perfect to causea certain degree of pressure in the sump I8 `and thereby force a portionof the oil through the holes 20 in the bottom of the cartridge 24. Afterenteringthe cartridge the t they 'provide cartridge. The oil frombthsothrough the outlet orince' 2,I.,

In this connection it might be pointed out that the screens 33, 3l and4l,- which-..may.; be of ilne wire mesh or coarsel fabricQor'otherfforaminated material, servev four purposes: first', .screensvIl cleansing of the oil;

from a relatively largesurfacef thezne illtering material 43; thirdly,the extending screens 39 and 40 serve ythe frictional contact with thenne altering material 4s to'msintein the latter in position and preventvits being come pressed upwardly toward the top ofthe cartridge: by themanner of 'theirpcsitioning numerous, oil paths through the finefiltering material 43,all' of substantially the same length, so thatin'v operation there is no one path of easy flow, but on the contrarytheo'il'ilows uniformly through all parts of` the cartridge.`

In the foregoing description of tiie'operation of the ydevice it hasbeenzassumed that lthe oil enters the device under optimum andvsubstantially and fourthlyl constant pressure conditions. Itv isimportant' in a filter of this type that the oil pressure inthefiltering cartridge be' maintained'at, or :at least below, apredetermined value, for if the pressure which thecartridge is designed.some packing of the ltering material will result; and dirty oil may beforced out of the cartridge'as wateris squeezed y out of a sponge.Inan'internal combustion en-V gine, a constant optimum. pressure-willnot pre?l vail, for the pressure of the oil will vary over a widefrangedepending upon the speed of the en'- f gine. The deviceautomaticallyjcompensates for changes of pressure andavoidsa forcibleejection of dirty oil in the following manner. Spring 34 in urging therim Zlofthe' cartridge into seated relationship Vwith the ,shoulder I4causes a certain pre-determined pressure to be-established inv the `sumpIl, the spring 34 being of such a strength as to establish a backpressure best aggapted forthe successful operation of the filter- Y ateat the oil pressure obtaining'a't moderate enoil willfiiow,` rathereasily and quickly up the double side screen 39 lying directly withintheV cylindrical surface of the cartridge,- whereby it will be broughtinto contact with asubstantially iarge area of the 'ltering element 43.Thereafter the oil will be urged upwardly through the filtering element43, through the felt disc 42, the top screen 4I and out throughthe'openings 3l in the top of the cartridge. A substantial part oftheoil will iiow through the filtering material to the screen core 4l,from whence it will flowV out the cartridge through the central part ofthe After having passed through the cartridge 24 theoil will flowacrossfthetop thereof and downwardly in the space 1l between the casingII and the sides of Vthe cartridge,pwhere it will meet the oil whichl.has iiowed out from under the bottom of the gine speed and .the springl34 will 'be selected to maintain the cartridge 24 on its seat at this`pressure.- At higher engine speeds the device will operate with thecartridge 24slightly raised from its seat.

The yielding seal between the rim 28 vof the cartridge and the shoulderI4 of the casing I I and the resulting valve action of the cartridge 24has also an important and beneficial eect upon the cold weather oprationof the device. If, in the wintertime, the engine and oil filter have notbeen in use for a short .per-lod, both will have assumed atmospherictemperature. This temperature may be so low that the oil within thecartridge will have somewhat congealed and become so, high in viscosityas to render the filtering cartridge ibstantially'impermeable. Under'these condions escape greater l than that for.-

material in the-cartridge. Should the oil be ydelivered to the casing IIat a substantially it would be advisable to provide meansr whereby theviscous oil is not forced through the container 2l, thereby causing'undue packing of the fineA filtering material 43. It would likewise beadvantageous to provide meanswhereby the cartridge may be heated to sucha temperature as will allow the proper operation thereof.

The device illustrated accomplishes each of these objects in thefollowing manner: inasmuch as the cold oil within the cartridge 24partially or wholly prevents a flow of oil through the cartridge theback pressure in the sump i8 is substantially increased. This increasedback pressure causes the cartridge 24 to raise up from the bottom of thecontainer, flexing spring A34 somewhat, and thereby permitting the oilto flow past the aperture then existing between the rim 25 and theshoulder I4, thence upwardly in space 26 between the cartridge 24 andthe inner wall of the casing il and out through the outlet orice 2|. Inthis manner cold and viscous oil is not forceably driven through thefiltering cartridge 2|. As the engine continues to operate the oiltemperature rises rather rapidly. This warm oil flowing upwardly betweenthe cartridge and the inner wall of the casing and being in contact withthe cartridge 24 throughout its entire surface, quickly transfers heatto the interior of the cartridge and restores the oil therein tooperating temperature, at which time the ltering material becomespermeable andthe passage of oil therethrough begins to take place.Simultaneously, the back pressure in the sump I8 is reduced and thespring 34 urges the cartridge down into normal operating position,thereby closing the gap between the edge 25', the shoulder Il andrestoring the device to normal operating conditions wherein most of theoil delivered to the device passes through the nltering cartridge 2l andis filtered.- l

It will be noted that the ltering cartridge 2l can easily and -quicklybe removed from the device when it has become saturated with impuritiesremoved from oil and a new cartridge substituted. The operation involvesmerely the loosening and removal of the cross piece 21, the removal ofthe coverplate I2 and the substitution of anew cartridge for the oldone. It is unnecessary to detach the oil connections to and from thedevice.

Though I have described but one adaptation of the 'invention and haveshown its use with par- `ticular reference to internal combustionengines, it is understood that the device is susceptible to numerousother uses and to the filtering of fluids other than engine oil and itis likewise 'understood that numerous modifications may be made in thestructural features of the invention without in' any way departing fromthe scope of the invention as defined in the appended claims.

I claim:

1. A filtering cartridge for a nlter of the class described comprising acontainer of impermeable material, the inlet end of said container beingperforated and the outlet end of said container being perforated, aforaminated screen directly inwardly of said inlet end, a secondforaminated screen within said container and adjacent the side wallsthereof and extending from said inlet end partway towards said outletendI a core of mesh-like material within said container and beginning ata point spaced from said inlet end and extending centrally in saidcartridge tosaid outlet end and iine filtering material substantiallynlling the remaining portion of-said container.

2. A altering cartridge ma mier orv the class described comprising acontainer of impermeable material. the inlet end of said container being-perforated and the outlet end of said container being perforated, aforaminatedv screen directly inwardly of said inlet end, a foraminatedscreen within said container and adjacent the side walls thereof andextending from said inlet portion partway towards said outlet portion, acore'of

